Diagnosis and treatment of carcinosarcoma of the renal pelvis: A case report.

Carcinosarcoma is a rare type of renal pelvis malignancy, the diagnosis of which requires the presence of malignant epithelial and mesenchymal components. The prognosis of this disease is extremely poor due to its rapid progression and widespread metastases. The present study describes a case of carcinosarcoma involving the right renal pelvis in a 73-year-old female who presented with intermittent hematuria and right-flank pain that had persisted for one month. Computed tomography revealed a 2.4×2.5 cm mass in the right renal pelvis, which was diagnosed as a right renal pelvic tumor. Laparoscopic radical resection of the right kidney and ureter was performed. Following surgery, immunohistochemical analysis showed positive reactions for epithelial and mesenchymal markers. Based on these findings, the patient was diagnosed with carcinosarcoma. Thus, immunohistochemical analysis is a critical method for the accurate diagnosis of carcinosarcoma.